From your question, it looks like you are filing for an employment based green card? If so, being out of status in the past will cause an issue. How many months you were out of status? If it is less than 180 days, you can leave the US and re-enter. Then, you will be pardoned. If it is more than 180 days, you aren't eligible for employment based green card. If it is through marriage/asylum, etc. then your past out of status won't be an issue.